package dsl

import (
	"strings"
	"testing"
)

func TestParseBuildBlockMinimal(t *testing.T) {
	src := `
build_defaults {
    language = "c"
    standard = "c11"
    sources  = "*.c"
    output   = "solution"
    warnings = strict
}

build "release" {
    profile = release
}

build "debug" {
    profile = debug
}

group("g1") {
    weight = 1.0
    test("t1") {
        stdout = "ok\n"
    }
}
`
	f, _, err := Parse(src)
	if err != nil {
		t.Fatalf("parse: %v", err)
	}

	if f.BuildDefaults == nil {
		t.Fatal("BuildDefaults not populated")
	}
	if f.BuildDefaults.Language != "c" {
		t.Errorf("language = %q", f.BuildDefaults.Language)
	}
	if f.BuildDefaults.Standard != "c11" {
		t.Errorf("standard = %q", f.BuildDefaults.Standard)
	}
	if len(f.BuildDefaults.Sources) != 1 || f.BuildDefaults.Sources[0] != "*.c" {
		t.Errorf("sources = %v", f.BuildDefaults.Sources)
	}
	if f.BuildDefaults.Output != "solution" {
		t.Errorf("output = %q", f.BuildDefaults.Output)
	}
	if f.BuildDefaults.Warnings != WarningsStrict {
		t.Errorf("warnings = %v", f.BuildDefaults.Warnings)
	}

	if len(f.Builds) != 2 {
		t.Fatalf("expected 2 builds, got %d", len(f.Builds))
	}
	if f.Builds[0].Name != "release" || f.Builds[0].Profile != ProfileRelease {
		t.Errorf("builds[0] = %+v", f.Builds[0])
	}
	if f.Builds[1].Name != "debug" || f.Builds[1].Profile != ProfileDebug {
		t.Errorf("builds[1] = %+v", f.Builds[1])
	}
}

func TestParseBuildLegacyStillWorks(t *testing.T) {
	src := `
build "cc -O2 solution.c -o solution"
timeout 5s

group("g1") {
    weight = 1.0
    test("t1") { stdout = "ok\n" }
}
`
	f, _, err := Parse(src)
	if err != nil {
		t.Fatalf("parse: %v", err)
	}
	if f.Build != "cc -O2 solution.c -o solution" {
		t.Errorf("legacy build = %q", f.Build)
	}
	if f.BuildDefaults != nil || len(f.Builds) != 0 {
		t.Errorf("structured fields should be empty for legacy form")
	}
}

func TestParseBuildOSOverride(t *testing.T) {
	src := `
build_defaults {
    language = "c"
    standard = "c11"
    sources  = "*.c"
    output   = "solution"
}

build "release" {
    profile = release
    linux   { extra = "-fPIC" }
    windows { extra = "/bigobj" }
}

group("g1") {
    weight = 1.0
    test("t1") { stdout = "ok\n" }
}
`
	f, _, err := Parse(src)
	if err != nil {
		t.Fatalf("parse: %v", err)
	}
	b := f.Builds[0]
	if b.Linux == nil || len(b.Linux.Extra) != 1 || b.Linux.Extra[0] != "-fPIC" {
		t.Errorf("linux override = %+v", b.Linux)
	}
	if b.Windows == nil || len(b.Windows.Extra) != 1 || b.Windows.Extra[0] != "/bigobj" {
		t.Errorf("windows override = %+v", b.Windows)
	}
	if b.Darwin != nil {
		t.Errorf("darwin override should be nil")
	}
}

func TestParseBuildPlatformsFilter(t *testing.T) {
	src := `
build "sanitized" {
    profile   = sanitized
    sanitize  = "address" "undefined"
    platforms = "linux"
    compilers = "gcc" "clang"
}

group("g1") {
    weight = 1.0
    test("t1") { stdout = "ok\n" }
}
`
	f, _, err := Parse(src)
	if err != nil {
		t.Fatalf("parse: %v", err)
	}
	b := f.Builds[0]
	if b.Profile != ProfileSanitized {
		t.Errorf("profile = %v", b.Profile)
	}
	if len(b.Sanitize) != 2 || b.Sanitize[0] != "address" || b.Sanitize[1] != "undefined" {
		t.Errorf("sanitize = %v", b.Sanitize)
	}
	if len(b.Platforms) != 1 || b.Platforms[0] != "linux" {
		t.Errorf("platforms = %v", b.Platforms)
	}
	if len(b.Compilers) != 2 {
		t.Errorf("compilers = %v", b.Compilers)
	}
}

func TestParseBuildDefineField(t *testing.T) {
	src := `
build "rel" {
    profile = release
    define("NDEBUG") = "1"
    define("VERSION") = "42"
}

group("g1") {
    weight = 1.0
    test("t1") { stdout = "ok\n" }
}
`
	f, _, err := Parse(src)
	if err != nil {
		t.Fatalf("parse: %v", err)
	}
	d := f.Builds[0].Defines
	if d["NDEBUG"] != "1" || d["VERSION"] != "42" {
		t.Errorf("defines = %v", d)
	}
}

func TestParseBuildErrors(t *testing.T) {
	cases := []struct {
		name string
		src  string
		want string
	}{
		{
			name: "unknown profile",
			src: `
build "x" { profile = ultra }
group("g") { weight=1.0 test("t"){ stdout="ok\n" } }
`,
			want: "unknown profile",
		},
		{
			name: "unknown warnings",
			src: `
build "x" { warnings = insane }
group("g") { weight=1.0 test("t"){ stdout="ok\n" } }
`,
			want: "unknown warnings",
		},
		{
			name: "unknown platform",
			src: `
build "x" { platforms = "bsd" }
group("g") { weight=1.0 test("t"){ stdout="ok\n" } }
`,
			want: "unknown platform",
		},
		{
			name: "nested OS override",
			src: `
build "x" {
    linux {
        windows { extra = "nope" }
    }
}
group("g") { weight=1.0 test("t"){ stdout="ok\n" } }
`,
			want: "cannot be nested",
		},
		{
			name: "duplicate OS override",
			src: `
build "x" {
    linux { extra = "-a" }
    linux { extra = "-b" }
}
group("g") { weight=1.0 test("t"){ stdout="ok\n" } }
`,
			want: "duplicate linux override",
		},
		{
			name: "unknown field",
			src: `
build "x" { magic = "yes" }
group("g") { weight=1.0 test("t"){ stdout="ok\n" } }
`,
			want: "unknown field",
		},
	}

	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			_, _, err := Parse(c.src)
			if err == nil {
				t.Fatal("expected error, got nil")
			}
			if !strings.Contains(err.Error(), c.want) {
				t.Errorf("error %q does not contain %q", err.Error(), c.want)
			}
		})
	}
}

func TestParseBuildMixedLegacyAndStructuredRejected(t *testing.T) {
	src := `
build "cc -O2 solution.c -o solution"
build "release" { profile = release }
group("g") { weight = 1.0 test("t") { stdout = "ok\n" } }
`
	_, _, err := Parse(src)
	if err == nil {
		t.Fatal("expected error mixing legacy and structured builds")
	}
	if !strings.Contains(err.Error(), "cannot mix") {
		t.Errorf("error %q does not mention mixing", err.Error())
	}
}

func TestParseBuildDuplicateNameRejected(t *testing.T) {
	src := `
build "release" { profile = release }
build "release" { profile = debug }
group("g") { weight = 1.0 test("t") { stdout = "ok\n" } }
`
	_, _, err := Parse(src)
	if err == nil {
		t.Fatal("expected error on duplicate build name")
	}
	if !strings.Contains(err.Error(), "duplicate") {
		t.Errorf("error %q does not mention duplicate", err.Error())
	}
}

func TestBuildConfigResolveMerge(t *testing.T) {
	defaults := &BuildConfig{
		Language: "c",
		Standard: "c11",
		Sources:  []string{"*.c"},
		Output:   "solution",
		Warnings: WarningsStrict,
	}
	b := &BuildConfig{
		Name:    "release",
		Profile: ProfileRelease,
		Extra:   []string{"-DFOO"},
		Linux: &BuildConfig{
			Extra: []string{"-fPIC"},
		},
		Windows: &BuildConfig{
			Extra:  []string{"/bigobj"},
			Output: "solution",
		},
	}

	linux := b.Resolve(defaults, "linux")
	if linux.Language != "c" || linux.Standard != "c11" {
		t.Errorf("linux defaults not merged: %+v", linux)
	}
	if linux.Profile != ProfileRelease {
		t.Errorf("linux profile = %v", linux.Profile)
	}
	if linux.Warnings != WarningsStrict {
		t.Errorf("linux warnings = %v", linux.Warnings)
	}
	if len(linux.Sources) != 1 || linux.Sources[0] != "*.c" {
		t.Errorf("linux sources = %v", linux.Sources)
	}
	if len(linux.Extra) != 2 || linux.Extra[0] != "-DFOO" || linux.Extra[1] != "-fPIC" {
		t.Errorf("linux extra = %v", linux.Extra)
	}

	windows := b.Resolve(defaults, "windows")
	if len(windows.Extra) != 2 || windows.Extra[0] != "-DFOO" || windows.Extra[1] != "/bigobj" {
		t.Errorf("windows extra = %v", windows.Extra)
	}

	darwin := b.Resolve(defaults, "darwin")
	if len(darwin.Extra) != 1 || darwin.Extra[0] != "-DFOO" {
		t.Errorf("darwin extra (no override) = %v", darwin.Extra)
	}

	if len(b.Extra) != 1 {
		t.Errorf("receiver mutated: %v", b.Extra)
	}
}

func TestParseToolchainsBlock(t *testing.T) {
	src := `
toolchains {
    gcc   { platforms = "linux" }
    clang {
        platforms = "linux" "windows"
        binary    = "clang-17"
        class     = gnu
    }
    msvc  { platforms = "windows" }
    nvcc  {
        platforms = "linux"
        class     = gnu
    }
}

build "release" { profile = release }

group("g") { weight = 1.0 test("t") { stdout = "ok\n" } }
`
	f, _, err := Parse(src)
	if err != nil {
		t.Fatalf("parse: %v", err)
	}
	if len(f.Toolchains) != 4 {
		t.Fatalf("expected 4 toolchains, got %d", len(f.Toolchains))
	}
	gcc := f.Toolchains[0]
	if gcc.Name != "gcc" || len(gcc.Platforms) != 1 || gcc.Platforms[0] != "linux" {
		t.Errorf("gcc = %+v", gcc)
	}
	clang := f.Toolchains[1]
	if clang.Name != "clang" || len(clang.Platforms) != 2 || clang.Binary != "clang-17" || clang.Class != "gnu" {
		t.Errorf("clang = %+v", clang)
	}
	if clang.Platforms[0] != "linux" || clang.Platforms[1] != "windows" {
		t.Errorf("clang platforms = %v", clang.Platforms)
	}
	nvcc := f.Toolchains[3]
	if nvcc.Name != "nvcc" || len(nvcc.Platforms) != 1 || nvcc.Platforms[0] != "linux" || nvcc.Class != "gnu" {
		t.Errorf("nvcc = %+v", nvcc)
	}
}

func TestParseToolchainsErrors(t *testing.T) {
	cases := []struct {
		name string
		src  string
		want string
	}{
		{
			"missing platforms",
			`toolchains { gcc { } }
			 group("g") { weight=1.0 test("t") { stdout="ok\n" } }`,
			"platforms is required",
		},
		{
			"unknown platform",
			`toolchains { gcc { platforms = "bsd" } }
			 group("g") { weight=1.0 test("t") { stdout="ok\n" } }`,
			"unknown platform",
		},
		{
			"unknown class",
			`toolchains { gcc { platforms = "linux" class = llvm } }
			 group("g") { weight=1.0 test("t") { stdout="ok\n" } }`,
			"unknown compiler class",
		},
		{
			"duplicate toolchain",
			`toolchains {
                gcc { platforms = "linux" }
                gcc { platforms = "linux" }
            }
            group("g") { weight=1.0 test("t") { stdout="ok\n" } }`,
			"duplicate toolchain",
		},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			_, _, err := Parse(c.src)
			if err == nil {
				t.Fatal("expected error, got nil")
			}
			if !strings.Contains(err.Error(), c.want) {
				t.Errorf("error %q does not contain %q", err.Error(), c.want)
			}
		})
	}
}

func TestBuildConfigAppliesTo(t *testing.T) {
	cases := []struct {
		name     string
		b        BuildConfig
		os, cc   string
		expected bool
	}{
		{"no filters", BuildConfig{}, "linux", "gcc", true},
		{"os match", BuildConfig{Platforms: []string{"linux"}}, "linux", "gcc", true},
		{"os mismatch", BuildConfig{Platforms: []string{"linux"}}, "windows", "msvc", false},
		{"cc match", BuildConfig{Compilers: []string{"gcc", "clang"}}, "linux", "clang", true},
		{"cc mismatch", BuildConfig{Compilers: []string{"gcc"}}, "linux", "msvc", false},
		{"both match", BuildConfig{Platforms: []string{"linux"}, Compilers: []string{"gcc"}}, "linux", "gcc", true},
		{"os ok cc bad", BuildConfig{Platforms: []string{"linux"}, Compilers: []string{"gcc"}}, "linux", "clang", false},
	}
	for _, c := range cases {
		t.Run(c.name, func(t *testing.T) {
			got := c.b.AppliesTo(c.os, c.cc)
			if got != c.expected {
				t.Errorf("AppliesTo(%q, %q) = %v, want %v", c.os, c.cc, got, c.expected)
			}
		})
	}
}